Field of the Invention
The present invention relates to locating objects, and in particular to locating assets and people within institutional sites.
Description of Related Art
RTLS (real time location services) systems are commonly used to locate objects, such as assets or people, within institutional sites such as manufacturing plants, warehouses, healthcare facilities or retail stores.
A typical RTLS system includes an infrastructure of fixed active devices, each located at a known location, and movable active devices, each associated with a known object. The fixed and movable active devices are adapted to establish short-range communication via an ultrasonic, infrared or low-power RF signal, and at least one of the fixed or movable active devices connects via a network to report meetings between respective active devices. Each meeting report indicates that the current location of the object associated with the movable active device is in proximity to the known location of the fixed active device, thereby providing real time location information related to the respective object.
The resolution of the detected location can be improved in a variety of ways, such as: a shorter communication range and higher number of fixed active devices; analyzing the signal strength, sometimes is association with the battery level, for estimating the current distance between the reported devices; or using triangulation for analyzing a plurality of simultaneous short-range signals associated with a single movable active device and a plurality of fixed active devices.
A typical RTLS system requires substantial investment in sensing and communication infrastructures throughout the site. While some sites justify such investment by effectively and quickly locating critical equipment or personnel, and others show high returns from targeted advertising, there are still many other sites, that could benefit from quickly locating objects, and cannot afford or justify the expense associated with deploying the respective sensing and communication infrastructure of a common RTLS system.
The present disclosure comes to teach locating systems with highly reduced sensing and communication infrastructures, and some applications of such systems.